Maternal hemodynamics at 11-13 weeks' gestation and risk of pre-eclampsia

MATERNAL CARDIAC TWIST PRE-PREGNANCY: POTENTIAL AS A NOVEL MARKER OF PRE-ECLAMPSIA

Healthy pregnancy is characterised by progressive physiological adaptation of the maternal cardiovascular (CV) system that facilitates optimal fetal development. The adaptations that constitute a healthy or normal progression are not always evident, and, in particular, CV adaptation to pregnancy is highly individualised. Some women develop pregnancy-related CV dysfunction such as pre-eclampsia (PE). Typically, PE is diagnosed by the development of hypertension and proteinuria after 20 weeks of pregnancy and is the leading cause of maternal and perinatal mortality and morbidity. Despite continued efforts to improve the understanding of the aetiology, pathophysiology and subsequently treatment for the disease, CV changes in PE are not well understood. PE before 34 weeks (early onset PE) is believed to differ in pathogenesis from late onset PE (>34 weeks) and can be characterised by a haemodynamic profile of increased systemic vascular resistance (SVR) and lower cardiac output (CO). Early onset PE is more often associated with uteroplacental insufficiency and significant adverse maternal and perinatal outcomes. In contrast, late onset PE (>34 weeks) involves an increased CO and lower SVR and is less likely to be associated with uteroplacental insufficiency and adverse perinatal outcomes. It is not known if PE develops secondary to the CV maladaptation in pregnancy or if a preexisting CV dysfunction predisposes some women to develop PE. Screening, diagnosis and disease management would be vastly improved if more were known about the onset of the maladaptive process associated with PE. To date, a combination of maternal factors including medical history, body mass index, age, parity and blood pressure (BP) have been used to predict the development of PE. In the first trimester, arterial stiffness is significantly increased in women who develop PE. Current hypotheses speculate that CV dysfunction is evident very early in pregnancy in PE and precedes the clinical manifestation at a later stage but whether CV dysfunction is present before pregnancy remains to be elucidated.

Patterns of maternal vascular remodeling and responsiveness in early- versus late-onset preeclampsia

OBJECTIVE

We sought to assess vascular structure and function in early- and late-onset preeclampsia (PE) at the time of diagnosis.

STUDY DESIGN

We evaluated 100 PE cases subdivided into 50 early- and 50 late-onset cases according to gestational age at onset (</>34 weeks), and 100 controls paired by maternal age and gestational age at scan with cases. Carotid intima-media thickness (IMT), distensibility, and circumferential wall stress together with inferior vena cava (IVC) collapsibility were assessed by ultrasound.

RESULTS

Early PE was characterized by increased carotid IMT diameters, and arterial stiffness with no significant changes in IVC parameters as compared to normotensive pregnancies. Late PE was characterized by significantly increased carotid IMT and lumen diameters as compared to controls while arterial stiffness, as expressed by distensibility, did not provide pronounced changes. A significant decrease of IVC collapsibility index was also observed in late PE as compared to controls.

CONCLUSION

The current data suggest that distinct vascular adaptations in early and late PE could reflect different pathophysiologic mechanisms. Future studies are warranted to further assess the complex etiologies and clinical expressions of the 2 entities.

Preeclampsia is a biomarker for vascular disease in both mother and child: the need for a medical alert system

This paper reviews the literature pertaining to the impact of preeclampsia not only on the mother but particularly on the children. The review points to the higher blood pressure in children born to preeclamptic mothers compared to controls, their increased tendency to suffer strokes, the reduction in their cognitive ability, and their vulnerability to depression. Mechanisms that may induce these changes are emphasized, particularly the placental vascular insufficiency and the resulting hypoxic and proinflammatory environments in which the fetus develops. The hypothesis proposed is that these changes in the fetal-placental environment result in epigenetic programming of the child towards a higher propensity for vascular disease. The review's main recommendation is that, within ethical boundaries, the medical records of individuals born to preeclamptic mothers should clearly indicate this event and should be made available to the affected individuals so that preventive measures against vascular complications and lifestyle changes that may mitigate the latter can be instituted.

Maternal hemodynamics at 11-13 weeks of gestation and preterm birth

OBJECTIVE

Women who experience preterm birth (PTB) are at increased risk of cardiovascular morbidity and mortality in the subsequent decades. Individuals with cardiovascular disorders have increased central aortic systolic blood pressure (SBP(Ao)) and arterial stiffness, assessed by pulse wave velocity (PWV) and augmentation index (AIx). The aim of this screening study was to evaluate SBP(Ao), PWV and AIx at 11-13 weeks' gestation in women who delivered preterm.

METHODS

This was a prospective study in singleton pregnancies at 11 + 0 to 13 + 6 weeks' gestation. Maternal history and characteristics were recorded, and PWV, AIx and SBP(Ao) were measured. We compared these parameters in women who had spontaneous (n = 244) or iatrogenic (n = 110) PTB before 37 weeks' gestation and before 34 weeks with those in women who had term delivery (n = 7489).

RESULTS

Compared with women who had term delivery, women who had iatrogenic PTB had significantly higher AIx (1.08 (interquartile range (IQR), 0.91-1.27) multiples of the median (MoM), vs. 1.00 (IQR, 0.86-1.16) MoM) and SBP(Ao) (1.06 (IQR, 0.98-1.15) MoM vs. 1.00 (IQR, 0.93-1.07) MoM). However, there was no significant difference in AIx, PWV or SBP(Ao) between those who had spontaneous PTB and those who had term delivery. These findings were similar for those who had PTB at < 34 and < 37 weeks' gestation.

CONCLUSION

Women who had iatrogenic PTB, but not those who had spontaneous PTB, have increased SBP(Ao) and arterial stiffness that is apparent from as early as the first trimester of pregnancy.